Adhesive compositions have been used to bond windows into buildings and vehicles. Examples of adhesives useful for these applications are described in Rizk, U.S. Pat. No. 4,780,520; Bhat, U.S. Pat. No. 5,976,305; Bhat, U.S. Pat. No. 5,922,809; Hsieh et al, U.S. Pat. No. 6,015,475; Zhou, U.S. Pat. No. 6,709,539; Rosenberg et. al., U.S. Pat. No. 7,226,523; Wu, U.S. Pat. No. 6,512,033; Zhou, U.S. Pat. No. 7,101,950; Zhou, U.S. Pat. No. 7,361,292; Nakata, et al., U.S. Pat. No. 6,657,035, Golombowski et al., U.S. Pat. No. 8,236,891 and Bosshard et al., CA 2,564,992. In automobile factories windows are installed using robots and computer controlled processing which facilitates the use of a variety of high performance adhesives, for instance, nonconductive adhesives and high modulus adhesives. The speed of cure is not a significant issue because new vehicles are not driven any significant distance for several days after window installation.
In contrast, when a vehicle needs a window replaced, it is often driven shortly after. The replacement is often performed in a remote location by an installer working from a vehicle or otherwise under uncontrolled conditions. Consequently, speed of cure is important as the vehicle owner desires to drive the vehicle as soon as possible after installation of the window. Adhesives useful in replacing windows for vehicles which facilitate fast drive away times are also known; see Bhat, U.S. Pat. No. 5,976,305; Zhou, U.S. Pat. No. 6,709,539 and Rosenberg et al., U.S. Pat. No. 7,226,523. These adhesives typically are polyurethane based with isocyanate functional prepolymers that require primers to enable the adhesion of the adhesive to the window and also give UV protection to the adhesive. The primers generally require further isocyanate compounds to facilitate the bonding of the adhesive to the glass. These primers are typically referred to as black primers because of the necessity to absorb UV light. These adhesives could have further improved performance to allow for faster drive away times and performance in the application. Generally, the performance of the adhesive in the application correlates with the impact resistance in Joules (J) with respect to time and shear (G) modulus (a measure of stiffness).
Consequently, it would be desirable to have a rapid drive away adhesive for bonding glass into a structure that has the required characteristics (such as high modulus and nonconductive nature), exhibits fast safe drive away times (fast impact strength development) when applied under a wide range of environmental conditions, does not require expensive ingredients, has acceptable sag and string when applied and long shelf life, while also not requiring a primer or other pretreatment containing isocyanates.